In a message dated 5/29/03 12:32:34 PM Pacific Daylight Time,
tombaugh@discoverynet.com writes:
> The cost of 3500 pound or even 4000 Pound mix is not significant in the
> large scheme (guessing $1 / yd). The pour is a relatively small and the
> price will be proportionately small. We pour 4000 pound concrete almost
> exclusively. YES it is overkill! However, the tradeoff is in workability.
> Stronger concrete has more of the expensive stuff.. the glue.. the Portland
> Cement and that is what makes the mixure "creamy" and easy to work. Too
much
> water can "appear" to give these properties but good concrete is good
> concrete. Add water and increase slump (good description below). but good
> concrete (4000 pound mix) will have a good slump (lower number) because it
> has more GLUE.
Another reason for using 4000# mix is that it'll cure to the specified
3000# fairly quickly - in a couple of days. This means you can load the base
much earlier than waiting for the 3000# mix to cure to 3000#.
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for commercial and amateur
|